Gold-Standard Accuracy.
Built for the Long Run.

Frontier X2 delivers advanced heart rate tracking, powered by continuous ECG, so you stay in the right zones.
Buy Frontier X2

Gold-Standard Accuracy.
Built for the Long Run.

Frontier X2 delivers advanced heart rate tracking, powered by continuous ECG, so you stay in the right zones.
Buy Frontier X2

Gold-Standard Accuracy.
Built for the Long Run.

Frontier X2 delivers advanced heart rate tracking, powered by continuous ECG, so you stay in the right zones.
Buy Frontier X2

The Science Of Precision

Wrist-based HR fails when you need it the most

ECG
  • Direct electrical heart signal measurement from the chest
  • High-quality ECG signal even during motion and sweat
  • Gold standard heart rate accuracy during high-intensity efforts
  • True beat-to-beat HRV measurement
  • Precise Zone 2 tracking guided by VT1 - VT2  zones
PPG
  • Optical blood flow-based heart rate estimation at the wrist
  • Higher signal variability during motion or loose contact
  • Lower reliability during sprints and intervals
  • Less precise HRV measurements due to signal noise
  • Estimates Zone 2 using standard heart rate-based zones

why ECG grade HR matters for a marathon

why ECG grade HR matters for a marathon

ECG grade accuracy helps you stay within your true target zone instead of unintentionally drifting into higher intensity efforts.

Inaccurate heart rate readings can make runners push harder than their body can safely sustain, increasing fatigue and physiological stress.

Consistent heart rate data helps maintain disciplined pacing without early burnout or late race collapse.

Chest-based ECG signals remain reliable during intense running conditions where wrist sensors may struggle.

Accurate heartbeat detection enables meaningful HRV insights to guide recovery and training load.

Precise Zone 2 tracking ensures endurance sessions actually stay aerobic rather than drifting into higher stress zones.

Why Frontier X2 is built for marathon prep

Why Frontier X2 is built for marathon prep

Why Frontier X2 is built for marathon prep

Why Frontier X2 is built for marathon prep

  • Accurate heart rate across long runs and high-intensity intervals
  • Real time alerts whenever you cross your Max/ Min HR
  • Precise Zone 2 based training, guided by VT1 - VT2
  • Breathing Rate + Strain insights for pacing decisions
  • Most reliable VO₂ Max and recovery trends through advanced HRV

Upgrade to World's First Smart Heart Monitor

Our Lowest Price Ever

Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2

  • 24/7 Continuous ECG during 20+ activities
  • Syncs with Apple Health, Garmin & more via BLE Syncs with Apple Health, Garmin & more via bluetooth 5.0
  • Lightweight. Sweat & water-resistant. (IP67)
  • Superior battery life for 14 days on typical usage
£449
Inclusive of VAT.
OR
£28 /month*
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Measure The Metrics That Matter

Heart Rate

Heart Rate
VO₂ Max
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VO₂ Max
VT1-VT2
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VT1-VT2
Strain Monitoring

Strain Monitoring
Training Load

Training Load
Body Shock

Body Shock
Heart Rate Zones

Heart Rate Zones
Breathing Rate

Breathing Rate
Step Cadence

Step Cadence
Calorie Tracking

Calorie Tracking
Readiness Score
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Readiness Score
Sleep Analysis
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Sleep Analysis
Heart Rate Variability

Heart Rate Variability
Continuous ECG

Continuous ECG

Trusted by Elite Marathon Runners and Olympic Athletes

Paula Radcliffe
(Former Women’s World Marathon Record Holder for 16 Years)
Mark Allen
(Six-Time Ironman World Champion)
Stephen Scullion
(Irish Olympic Athlete)

Try it risk free for 14 days and 1 year warranty

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